Chapter Objectives

1. Diagram energy flow through the biosphere
2. Describe the overall summary equation for cellular respiration
3. Distinguish between substrate-level phosphorylation and oxidative phosphorylation
4. Explain how exergonic oxidation of glucose is coupled to endergonic synthesis of ATP
5. Define oxidation and reduction
6. Explain how redox reactions are involved in energy exchanges
7. Define coenzyme and list those involved in respiration
8. Describe the structure of coenzymes and explain how they function in redox reactions
9. Describe the role of ATP in coupled reactions
10. Explain why ATP is required for the preparatory steps of glycolysis
11. Describe how the carbon skeleton of glucose changes as it proceeds through glycolysis
12. Identify where in glycolysis the sugar association, substrate-level phosphorylation, and reduction of coenzymes occur
13. Write a summary equation for glycolysis and describe where it occurs in the cell
14. Describe where pyruvate is oxidized to acetyl CoA, what molecules are produced , and how pyruvate links glycolysis to the Krebs cycle
15. Explain at what point during cellular respiration complete oxidation of glucose occurs
16. Explain how the exergonic "slide" of electrons down the electron transport chain is coupled to the endergonic production of ATP by chemiosmosis
17. Describe the process of chemiosmosis
18. Explain how membrane structure is related to membrane function in chemiosmosis
19. Describe the fate of pyruvate in the absence of oxygen
20. Explain why fermentation is necessary
21. Distinguish between aerobic and anaerobic metabolism
22. Describe how food molecules other than glucose can be oxidized to make ATP
23. Describe evidence that the first prokaryotes produced ATP by glycolysis
24. Explain how ATP production is controlled by the cell and what role the allosteric enzyme, phosphofructokinase, plays in this process

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25. Distinguish between autotrophic and heterotrophic nutrition
26. Distinguish between photosynthetic autotrophs and chemosynthetic autotrophs
27. Describe the location and structure of the chloroplast
28. Explain how chloroplast structure relates to its function
29. Write a summary equation for photosynthesis
30. Explain van Niel's hypothesis and describe how it contributed to our current understanding of photosynthesis
31. Explain the role of REDOX reactions in photosynthesis
32. Describe the wavelike and particle-like behaviors of light
33. Explain why the absorption spectrum for chlorophyll differs from the action spectrum for photosynthesis
34. List the wavelengths of light that are most effective for photosynthesis
35. Explain what happens when chlorophyll or accessory pigments absorb photons
36. List the components of a photosystem and explain their functions
37. Trace electron flow through photosystems I and II
38. compare cyclic and noncyclic electron flow and explain the relationship between these components of the light reaction
39. Summarize the light reactions with an equation and describe where they occur
40. Describe important differences in chemiosmosis between oxidative phosphorylation in mitochondria and photophosphorylation in chloroplasts
41. Summarize the carbon-fixing reactions of the Calvin cycle and describe changes that occur in the carbon skeleton of the intermediates
42. Describe the role of ATP and NADPH in the Calvin cycle
43. Describe what happens to rubisco when the O_{2 concentration is much higher than CO2}
44. Describe the major consequences of photorespiration
45. Describe two important photosynthetic adaptations that minimize photorespiration
46. Describe the fate of photosynthetic products

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Chapter Terms:

Chapter Outline Framework

1. Principles of Energy Conservation
   1. Cellular respiration and fermentation are catabolic (energy-yielding) pathways
   2. Cells must recycle the ATP they use for work
   3. Redox reactions release energy when electrons move closer to electronegative atoms
   4. Electrons "fall" from organic molecules to oxygen during cellular respiration
   5. The "fall" of electrons during respiration is stepwise, via NAD+ and an electron transport chain
2. The Process of Cellular Respiration
1. Respiration involves glycolysis, the Krebs cycle, and electron transport
2. Glycolysis harvests chemical energy by oxidizing glucose to pyruvate
3. The Krebs cycle completes the energy-yielding oxidation of organic molecules
4. The inner mitochondrial membrane couples electron transport to ATP synthesis
5. Cellular respiration generates many ATP molecules for each sugar molecule it oxidizes
3. Related Metabolic Processes
   1. Fermentation enables some cells to produce ATP without the help of oxygen
   2. Glycolysis and the Krebs cycle connect to many other metabolic pathways
   3. Feedback mechanisms control cellular respiration
4. Photosynthesis in Nature
   1. Plants and other autotrophs are the producers of the biosphere
   2. Chloroplasts are the sites of photosynthesis in plants
5. The Pathways of Photosynthesis
   1. Evidence that chloroplasts split water molecules enabled researchers to track atoms thorough photosynthesis
   2. The light reactions and Calvin cycle cooperate in converting light energy to the chemical energy of food
   3. The light reactions transform solar energy to the chemical energy of ATP and NADPH
   4. The Calvin cycle uses ATP and NADPH to convert CO₂ to sugar
   5. Alternative mechanisms of carbon fixation have evolved in hot, arid climates
   6. Photosynthesis is the biosphere's metabolic foundation

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